Multi-polarization planar antenna

Abstract

A dual polarization planar antenna comprising a first layer comprising a first patch, a second layer beneath the first layer comprising a first feed line for coupling a first signal to the first patch and a second feed line for coupling a second signal to the first patch such that the first patch radiates a field that has two different polarizations, and a third layer comprising first and second coupling discs electrically connected to the first feed line and third and fourth coupling discs electrically connected to the second feed line, wherein the first and second discs are electrically coupled to each other by a first half wavelength conductor and the third and fourth discs are electrically coupled the each other by a second half wavelength conductor, the first and second half wavelength conductors not being disposed in the second layer.

1. A dual polarization planar antenna comprising:
 a first layer comprising a first patch; 
 a second layer beneath the first layer comprising a first feed line for coupling a first signal to the first patch and a second feed line for coupling a second signal to the first patch such that the first patch radiates a field that has two different polarizations; and 
 a third layer comprising first and second coupling discs electrically connected to the first feed line and third and fourth coupling discs electrically connected to the second feed line; 
 wherein the first and second discs are electrically coupled to each other by a first half wavelength conductor and the third and fourth discs are electrically coupled to each other by a second half wavelength conductor, the first and second half wavelength conductors not being disposed in the second layer. 
 
     
     
       2. The antenna of  claim 1  further comprising fourth and fifth layers comprising a ground plane, the fourth and fifth layers sandwiching the second layer. 
     
     
       3. The antenna of  claim 2  wherein the first and second half wavelength conductors comprise transmission lines and wherein the first and second half wavelength conductors are not between the fourth and fifth layers. 
     
     
       4. The antenna of  claim 1  wherein the first and second half wavelength conductors are in the third layer. 
     
     
       5. The antenna of  claim 4  wherein the third layer comprises a first sub-layer including the first and second discs and the first half wavelength conductor and a second sub-layer comprising the third and fourth discs and the second half wavelength conductor. 
     
     
       6. The antenna of  claim 5  wherein the first and second discs and the first conductor are coplanar with each other and wherein the third and fourth discs and second conductor are coplanar with each other. 
     
     
       7. The antenna of  claim 5  wherein the first disc is electrically coupled to the first feed line by a first conductive via extending between the second layer and the first sub layer of the third layer, and the third disc is electrically coupled to the second feed line by a second conductive via extending between the second layer and the second sub-layer of the third layer. 
     
     
       8. The antenna of  claim 7  wherein each layer, including each sub-layer, further comprises an insulating material. 
     
     
       9. The antenna of  claim 8  wherein the insulating material of each layer comprises at least RF board. 
     
     
       10. The antenna of  claim 9  further comprising at least one layer of foam spacer. 
     
     
       11. The antenna of  claim 1  further comprising:
 a seventh layer comprising a second patch. 
 
     
     
       12. The antenna of  claim 1  further comprising eighth and ninth layers, wherein the first half wavelength conductor is in the eighth layer and the second half wavelength conductor is in the ninth layer. 
     
     
       13. The antenna of  claim 12  wherein the first disc is electrically coupled to the first feed line by a first conductive via extending between the second and third layers and wherein the first conductive line has a first end coupled to an intermediate point in the first conductive via and a second end coupled to a third conductive via extending between the eighth layer and the third layer and connected to the second disc, and wherein the second conductive line has a first end coupled to an intermediate point in the second conductive via and a second end coupled to a fourth conductive via extending between the ninth layer and the third layer and connected to the fourth disc. 
     
     
       14. The antenna of  claim 13  wherein the eighth and ninth layers are disposed between the second and third layers. 
     
     
       15. The antenna of  claim 1  wherein the first feed line and first conductor are parallel to each other and wherein the second feed line and second conductor are parallel to each other. 
     
     
       16. The antenna of  claim 15  wherein the first feed line and first conductor are orthogonal to the second feed line and second conductor. 
     
     
       17. The antenna of  claim 1  wherein the first and second feed lines comprise strip lines. 
     
     
       18. The antenna of  claim 1  further comprising at least one insulating layer disposed between each of the first, second, and third layers.